Cartridge adapter

ABSTRACT

A cartridge adapter permitting the use of rimfire ammunition in center-fire weapons. The adapter comprises a cartridge-shaped housing with an upper casing for supporting a rimfire cartridge and a lower casing containing a firing pin assembly.

United States Patent Irving W. Glater 277 North Quaker Lane, West Hartford, Conn. 061 19 Nov. 12, 1969 Aug. 10, 1971 Inventor App! No. Filed Patented CARTRIDGE ADAPTER 10 Claims, 2 Drawing Fig.

F42b 9/20, F42b 13/20 Field of Search II 4, i

Primary Examiner-Robert F. Stahl Anorney Fishman and Van Kirk ABSTRACT: A cartridge adapter permitting the use of rimfire ammunition in center-fire weapons. The adapter comprises a cartridge-shaped housing with an upper casing for supporting a rimfire cartridge and a lower casing containing a firing pin assembly.

PATENTED M1089?! 3.598.053

z" gag-Q gm AMM- INVENTOR. IRVING W. (SLATER ATTORNEYS CARTRIDGE ADAPTER BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cartridge adapters. More particularly the present invention is directed to cartridgt adapters of the type permitting the use of rimfire ammunition in weapons designed for center-fire ammunition. Accordingly. the general objects of the present invention are to provide a novel and improved instrument of such character.

2. Description of the Prior Art Technological advances in weapon designs have resulted in both an increase in the fire power of center-fire cartridges and the discontinuation of obsolete types of cartridges. This has led to a twofold problem in that the new, high power cartridges cannot be used at indoor or restricted target ranges and many center-fire cartridge sizes formerly available have been discontinued. However, there exist rimfire cartridges incorporating projectiles of appropriate size to function accurately through the bores of rifles chambered for the obsolete cartridges. Previously owners of these rifles were forced to abandon the shooting of their weapons or reload their own cartridges. It is also to be noted that, even if circumstances permit use of center-fire ammunition, the cost of this ammunition is substantially higher than rimfire ammunition of the same size.

A number of cartridge adapters have been proposed in the prior art. However, these adapters have proved to be impractical for a number of reasons. Some models required use 01' tools to remove the spent cartridge from the adapter and mounted the adapter firing pin such that a portion of the linear force supplied by the weapon firing pin was converted to rotational and/or radial energy thereby tending to jam the adapter firing pin nd reducing the amount of energy transmitted to the cartridge primer. Other models failed to provide a means for positively positioning the adapter firing pin and utilized a method of removing the spent cartridge which allowed the adapter to open during ejection from the weapon. Still other models contained no means for replacing the forward portion of the adapter and were limited by the high wear rates at this point to short service life.

An additional disadvantage of previous cartridge adapters has been the failure to provide a means for preventing holidays in the rim fire cartridges primer from causing a misfire.

A further serious disadvantage of the prior art resided in the fact that the apparatus available usually neither placed the adapted cartridge's projectile into the lead of the rifling of the rifle barrel nor supported the cartridge case closely. With either or both of these deficiencies, the accuracy capability of the weapon cannot be approached.

SUMMARY OF THE INV ENTION The present invention overcomes the disadvantage of the prior art and in so doing provides a reliable, dural le and manually reloadable cartridge adapter comprising a tubular upper casing, a firing pin support, a fork shaped hami ter and firing pin assembly, and a tubular lower casing. The:-e components are assembled in such a manner that both the upper casing and firing pin support position and provide support for a rimfire cartridge while the firing pin support and IO\ 'er casing slidably support the firing pin assembly. The hammer portion of the firing pin assembly is exposed to the weapon firing pin whose impact forces the hammer to move forward hereby propelling each tine of the firing pin along a passage, .iefined by a channel in the outer wall of the firing pin support 1nd the inner wall of the lower casing, until the end of each ti 1e contacts the primer of the rimfire cartridge. It is especial y to be noted that the adapter of the present invention, because of the configuration of the tabular upper casing, simulates the exterior dimensions of any standard center-fire cartridge.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be better understood and its numerous advantages will become apparent to those skilled in the art by reference to the accompanying drawing wherein like reference numerals refer to like elements in the various figures and in which:

FIG. 1 is a longitudinal assembled view, partly in section, of a preferred embodiment of the present invention containing a live cartridge.

FIG. 2 is an isometric, exploded view of the preferred embodiment of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, the cartridge adapter of the present invention has a tubular lower casing 10 in which a cylindrical firing pin support 12 is mounted by means of a locating pin 14. A fork shaped firing pin assembly; said assembly comprising a cylindrical hammer 16 and a two tined pin including integral left firing pin 18 and right firing pin 20; is slidably mounted within casing 10. The left firing pin 18 travels within a first passage defined by a left longitudinal groove 22, formed in the outer surface of support 12, and the inner surface of the lower casing 10. The right firing pin 20 travels within a second passage; the second passage being defined by a right longitudinal groove 24 in the outer surface ofsupport I2 and the inner surface of the lower casing 10. The

hammer portion 16 of the firing pin assembly, which is contacted by the firing pin of the weapon acting through aperture 26 in the base of casing 10, travels within lower casing 10 and is guided by a cylindrical depression 28 centrally located in the lower portion of the firing pin support 12. The depth of depression 28 is selected such that the hammer 16 will bottom locking pin 32, mounted radially on the outer wall ofthe firing pin support 12 near the upper edge of support 12, and an L- shaped channel 34 located near the lower end of the upper casing 30. The upper casing 30 is shaped internally so as to provide radial support to the sidewall of a rimfire type car'- tridge, indicated generally at 36, while positioning the cartridge 36 such that the upper face of the support 12 provides 7 support for the base of the cartridge 36. The shoulder 31 in casing 12 supports the forward side of the rim of the cartridge 36 and prevents forward motion of the cartridge when struck by the firing pins.

The lower casing 10, upper casing 30, carrier locating pin 14, and locking pin 32 are of such size and shape that the assembled adapter containing a live rimfire type cartridge simulates the dimensions of a center-fire cartridge. Also, because of the shaping of upper casing 30, and particularly of the necked down upper portion thereof, the projectile will be inserted into the bore of the weapon and thus will immediately be engaged by the rifling in the barrel when the cartridge is 1 fired. This is in contradistinction to the prior art wherein the projectile typically had to bridge a gap before entering the barrel.

In manufacture, the thin upper casing 30 will comprise a comparatively inexpensive aluminum extrusion. Due to its size and shape, upper casing 30 is susceptible to damage; both in the present invention and in the prior art. In the present invention, however, upper casing 30 may be readily replaced without severe economic penalty. This was not true in the prior art.

Lower casing 10 will typically be comprised of steel as will firing pin support 12. The firing pin assembly will be comprised of a U-shaped rod, typically steel music wire, which is received in a groove in a brass hammer 16. Use of brass or other soft metal for hammer 16 is in the interest of preventing damage to the firing pin of the weapon. The U-shaped rod which forms firing pins 18 and will typically be swaged to hammer l6 and the rod will be free to rotate so as to facilitate assembly of the adapter. The ends of the rod which strike the cartridge 36 will be formed into chisel shaped points.

In the operation of the cartridge adapter of the present invention, a rimfire cartridge 36 is placed in the upper casing against shoulder 31. The upper casing 30 is then locked onto the firing pin support 12 by engaging the locking pin 32 in the channel 34. The assembled adapter is then mounted in the chamber of a weapon.

Force transmitted from the weapon firing pin to the hammer 16 causes the hammer 16, left firing pin 18, and right firing pin 20 to move forward until the chisel shaped ends of the firing pins contact the primer of the rimfire cartridge thereby causing it to detonate.

Upon ejection from the weapon the upper casing 30 is removed from the carrier 12 by disengaging the lockin pin 32 from the channel 34. The spent cartridge 36 is then removed from the upper casing 30 which is inspected for damage prior to reuse.

Removal of a spent cartridge is usually achieved simply by allowing it to freely drop out of casing 30. If the cartridge should fail to drop out of the casing, removal is easily accomplished by placing the upper casing 30 on a flat surface, inserting a cylindrical rod or pencil of appropriate diameter into the small end of the upper casing and applying finger or hand pressure.

While a preferred embodiment has been shown and described, various modifications and substitutions may be made without departing from the spirit and scope of this invention. Accordingly, it is to be understood that this invention has been described by way of illustration rather than limitation.

What 1 claim is:

1. A cartridge adapter comprising:

a tubular lower casing;

a firing pin support mounted within the lower casing, said support extending beyond a first end of said lower casing;

a firing pin assembly slidably mounted within the lower casa tubular upper casing removably attached to the upper portion of the firing pin support, said upper casing abutting said first end of said lower casing when installed on said support and cooperating with sad lower casing to define a simulated cartridge having substantially smooth outer surfaces; and

means for positioning a cartridge within the upper ca sing.

2. A cartridge adapter as described in claim 1 whe ein the firing pin assembly comprises.

a cylindrical hammer; and

a U-shaped firing pin attached to the hammer.

3. A cartridge adapter as described in claim 2 wherein the cylindrical hammer is comprised of brass and the firing pin is comprised of steel.

4. A cartridge adapter as described in claim 2 wherein the firing pin support in combination with the lower casing defines:

a central passage in which the hammer is slidably mounted;

a pair oflongitudinal passages for guiding the firing pin.

5. A cartridge adapter as described in claim 1 wherein the firing pin support comprises:

a cylindrical support member mounted within the lower cas ing, a first end of said cylindrical support extending beyond said first end of said lower casing;

a first longitudinal channel formed in the outer wall of the cylindrical support, said first longitudinal channel, in combination with the lower casing defining a first longitudinal passage;

a second longitudinal channel formed in the outer wall of the cylindrical support, said second channel being oppositely disposed to the first longitudinal channel, said second longitudinal channel in combination with the lower casing defining the second longitudinal channel, said first and second passages guiding the movements of said firing pin assembly; and

a central recess formed in the second end of said cylindrical support.

6. The apparatus of claim 5 wherein said firing pin assembly comprises:

a cylindrical hammer dimensioned for movement in said recess; and t a pair of firing pins extending from said hammer, said pins being received in respective of said longitudinal channels.

7. A cartridge adapter as described in claim 6 wherein the means for positioning a cartridge comprises:

a transverse, annular support surface formed on the internal wall ofthe tubular upper casing.

8. A cartridge adapter as described in claim 7 wherein the lower casing contains a centrally located opening formed in the second end of said lower casing, said opening cooperating with the central recess in said support to define a central passage for movement ofsaid hammer.

9. A cartridge adapter as described in claim 8 further comprising:

means for removably attaching the upper casing to the upper portion of the firing pin support, said means including a bayonet type locking mechanism.

10. A cartridge adapter as described in claim 9 wherein the distance between the bottom surface of the central recess formed in the firing pin support and the transverse. annular, support surface is greater than the length of the firing pin. 

1. A cartridge adapter comprising: a tubular lower casing; a firing pin support mounted within the lower casing, said support extending beyond a first end of said lower casing; a firing pin assembly slidably mounted within the lower casing; a tubular upper casing removably attached to the upper portion of the firing pin support, said upper casing abutting said first end of said lower casing when installed on said support and cooperating with sad lower casing to define a simulated cartridge having substantially smooth outer surfaces; and means for positioning a cartridge within the upper casing.
 2. A cartridge adapter as described in claim 1 wherein the firing pin assembly comprises: a cylindrical hammer; and a U-shaped firing pin attached to the hammer.
 3. A cartridge adapter as described in claim 2 wherein the cylindrical hammer is comprised of brass and the firing pin is comprised of steel.
 4. A cartridge adapter as described in claim 2 wherein the firing pin support in combination with the lower casing defines: a central passage in which the hammer is slidably mounted; a pair of longitudinal passages for guiding the firing pin.
 5. A cartridge adapter aS described in claim 1 wherein the firing pin support comprises: a cylindrical support member mounted within the lower casing, a first end of said cylindrical support extending beyond said first end of said lower casing; a first longitudinal channel formed in the outer wall of the cylindrical support, said first longitudinal channel, in combination with the lower casing defining a first longitudinal passage; a second longitudinal channel formed in the outer wall of the cylindrical support, said second channel being oppositely disposed to the first longitudinal channel, said second longitudinal channel in combination with the lower casing defining the second longitudinal channel, said first and second passages guiding the movements of said firing pin assembly; and a central recess formed in the second end of said cylindrical support.
 6. The apparatus of claim 5 wherein said firing pin assembly comprises: a cylindrical hammer dimensioned for movement in said recess; and a pair of firing pins extending from said hammer, said pins being received in respective of said longitudinal channels.
 7. A cartridge adapter as described in claim 6 wherein the means for positioning a cartridge comprises: a transverse, annular support surface formed on the internal wall of the tubular upper casing.
 8. A cartridge adapter as described in claim 7 wherein the lower casing contains a centrally located opening formed in the second end of said lower casing, said opening cooperating with the central recess in said support to define a central passage for movement of said hammer.
 9. A cartridge adapter as described in claim 8 further comprising: means for removably attaching the upper casing to the upper portion of the firing pin support, said means including a bayonet type locking mechanism.
 10. A cartridge adapter as described in claim 9 wherein the distance between the bottom surface of the central recess formed in the firing pin support and the transverse, annular, support surface is greater than the length of the firing pin. 